Plant growth regulating agent

ABSTRACT

2-ethyl-6-methyl-N-(1&#39;-methoxyprop-2&#39;-yl)-N-chloroacetanilide is disclosed as plant growth regulating and herbicidal agent with improved stability in the soil.

CROSS-REFERENCE

This application is a continuation-in part of our application Ser. No.366,955, filed June 4, 1973 and now abandoned.

The present invention relates to2-ethyl-6-methyl-N(1'-methoxyprop-2'-yl)-N-chloroacetanilide having theformula I ##SPC1##

a process for its preparation as well as plant-growth regulating agentscontaining this compound as active ingredient and its use in theselective combatting of weeds in plant-cultures.

Various types of haloacetanilides have been described in the art asbeing herbicidally active.

In U.S. Pat. No. 3,442,945 it is stated that:

"It will be noted that the nitrogen-substituted α-haloacetanilides whichare nuclear-substituted with a tertiary alkyl group in one orthoposition and another substituent in the other ortho position possessunusual grass specifity and, furthermore, that these α-haloacetanilideshave unusually high activity at extremely low application rates."

In accordance with this statement2'-tert.butyl-2-chloro-N-ethoxyethyl-6'-ethylacetanilide of the formulaA ##SPC2## is highlighted inter alia as an example of a compound beingespecially active at low dosage levels. In example 85 of U.S. Patent No.3,547,620 and appendant Table IV it is shown that2-chloro-2'-tert.butyl-6'-ethyl-N-(ethoxymethyl)acetanilide of theformula A' ##SPC3##

exhibits a 25 % improvement in herebicidal activity over that of theabove compound A. Further herbicidal-test in tables V, VI and VIIcorroborate these findings and following conclusion is drawn:

"The difference in herbicidal effectiveness is directly related to thepresence of an alkoxymethyl, instead of an alkoxyethyl or alkoxypropylgroup, on the nitrogen atom of the acetanilide. It is immaterial, as isshown in this example, whether the halo is bromine or chlorine."

From the combined teachings of these patents it would follow thatchloro- and bromoacetanilides containing an ethoxymethyl rather than anethoxyethyl group on the nitrogen atom and particularily those with anortho tert. butyl group are likely to possess the most favourableherbicidal activity for practicle purposes. However, the closest analogdescribed in U.S. Pat. No. 3,547,620 is compound E shown hereinafter.Furthermore U.S. Pat. No. 3,739,024 shows that the conversion ofhaloacetanilides with thionophosphine sulfide producesHalothioacetanilides having particularily useful herbicidal properties.Halothioacetanilides containing the allegedly herbicidally lessadvantageous ethoxyethyl group at the nitrogen atom are exemplified.

Experience has now shown that in general the compounds described in theabove references while possessing useful herbicidal properties lacksufficient stability in the ground. It is desirable that a selectiveherbicide used to protect a plant culture should possess not only anappropriate weedicidal spectrum but also a duration of activity suchthat one application per crop season will suffice to keep the treatedlocus weedfree through to harvest.

A BROAD-SPECTRUM SELECTIVE HERBICIDE IS OF NO REAL PRACTICAL UTILITY IFIT BREAKS DOWN WITHIN 2 OR 3 WEEKS OF APPLICATION THUS REQUIRING SEVERALAPPLICATIONS PER SEASON WITH THE CONCOMMITENT INCREASE IN LABOUR ANDCOSTS.

A pre-emergent herbicide with sufficient in-soil durability avoids thenecessity of further herbicides post-emergent application.

The ideal selective herbicide possesses an activity spectrum proper tothe crop to be protected, a high weedicidal activity and a suitably longlife after application. These criteria and desiderata apply equally toplant-growth regulating substances. All have to be taken into accountwhen selecting a suitable herbicidal or plant-growth regulating agent.

It has now been found that the compound of the formula I in contrast toknown acetanilide derivates fully satisfies all the above describedrequirements.

The active substance according to the invention possesses very goodherbicidal activity against annual grasses such as Echinochloa andrelated plants of the genera Setaria, Digitaria, etc., against grassessuch as Lolium species and against many dicotyledonous weeds such asAmaranthus, Stellaria, Chrysanthemum, Sinapis etc., without causingdamage to the plant cultures in which it is intended to be used.Examples of such plants cultures are maize, sun flower, sugar beet,sugar cane, tobacco and potatoe, leguminous cultures such as soya,various types of ground nut (peanut), pea and various types of bean andalso cotton and Brassica species such as rape and cabbage. The activesubstance may be applied either before or after germination of the plantculture and of the weeds or grasses (pre- and postemergent treatment).Suitable rates for pre-emergent application lie between 0.1 and 10 kg ofactive substance per hectare. At lower levels the compound actsselectively. For example with rates as low as and in the region of 2kg/hectare weeds in a crop culture such as aforementioned are destroyedwhile the crop is left intact.

At higher rates the active substance acts as a total herbicide and maybe employed for example to prevent railway embankments, factory areas,roads etc. from becomming overgrown.

When used for post-emergent treatment the compound acts as aplant-growth regulator in that it will delay or inhibit the growth ofmany mono- or di- cotyledonous plants be they plant cultures or weeds.Thus the growth rate of grassland (comprising for example Poa pratensis,Agrostis tenuis, Festuca rubra) treated with 5 kg/hectare of activesubstance shortly after the first cutting in spring is reduced by halfan observation period of 60 days being used as a basis. The primaryconsequence of this activity is a reduction of the plant size inparticular of its height. Accompanying changes in plantmorphology may beobserved. As a direct result of the reduction in height the plant gainsin sturdiness, the leaves and stems grow stronger and in the case ofmonocotyledones the reduction of the internodal distance results ingreater resistance to bending and breaking. A further benefit of reducedgrowth in plant cultures and for example lawns, sports fields and othergrassed-over areas is the saving in manure and/or fertilizer and in thecase of the latter the reduced frequency at which they must be mown orscythed. A typical area of application would be to roadsides where theeasy maintenance of medium growth-height throughout the vegetationperiod is desirable. The active substance of the formula I may of coursebe used in conjunction with other active substances. Additionally thecompound I acts as an antisprouting agent on potatoes which are intendedfor storage or consumption. It also acts as fungicide to combatplantpathogenic fungi.

The compound of the formula I may be manufactured by reacting theN-substituted aniline of the formula II ##SPC4##

with a chloroacetylating agent, preferably an anhydride or halide ofchloroacetic acid.

The compound of the formula I may also be produced by reacting2-methyl-6-ethyl-aniline with a 2-halopropanol subsequentlychloroacetylating the obtained compound of the formula IIa ##SPC5##

preferably with an

anhydride or halide of chloroacetic acid and finally etherifying thefree OH group with methanol in acid medium, (e.g. in the presence ofHC1, H₂ SO₄) under mild conditions and in a conventional manner.

The reactions can be carried out in the presence or absence of solventsor diluents which are inert towards the reactants. Examples of suitablesolvents or diluents are:

aliphatic, aromatic or halogenated hydrocarbons, such as benzene,toluene, xylene, petroleum ether, chlorobenzene, methylene chloride,ethylene chloride, chloroform; ethers and ethereal compounds, such asdialkyl ethers, dioxan, tetrahydrofuran; nitriles, such as acetonitrile;N,N-dialkylated amides, such as dimethyl formamide; also dimethylsulphoxide, as well as mixtures of these solvents.

Suitable chloroacetylating agents are for example chloroaceticanhydride, and chloroacetic halides, such as chloroacetyl chloride.However, it is also possible to carry out the reaction usingchloroacetic acid, or its esters or amides. The reactions are carriedout at temperatures between 0° and 200°C, preferably between 20° and100°C. The chloroacetylation step is usefully carried out in thepresence of an acid binding agent (especially if chloroacetyl halidesare used). Suitable acid binding agents are: tertiary amines, such astrialkylamines, e.g. triethylamine, pyridine and pyridine bases, orinorganic bases, such as oxides and hydroxides, hydrogen carbonates andcarbonates or alkali and alkaline earth metals. Furthermore, it is alsopossible to use an excess of the corresponding aniline of the formula IIas acid binding agent.

Compounds homologous to formula II and hydroxyalkyl derivativeshomologous to formula IIa are known, e.g. from U.S. Pat. No. 2.381.071,2.759.943 as well as from Am. Soc. 84, 743 and Bull. Soc. Chim. France1962, 303 and 1965, 2037.

The starting material of the formula II may be manufactured for exampleby one of the following known methods:

a. condensation of 2-methyl-6-ethyl-aniline with methoxyacetone andsimultaneous or subsequent catalytic hydrogenation of the resultingazomethine of the formula III ##SPC6##

or

b. reaction of 2-methyl-6-ethyl-aniline with a compound of the formulaIV ##EQU1## wherein Y represents a halogen atom or another anionic groupin particular an arylsulphonate radical. Compounds of the formula IVwith a benzenesulphonate acid radical as Y are described e.g. in Can. J.Chem. 33, 1207, and those with a tosyloxy radical (CH₃ --C₆ H₄ --SO₃ --)in British patent 869,083. There are, of course, a number of otherprocesses for the manufacture of the starting materials of the formulaII from ortho-alkylated anilines.

The following Examples illustrates the invention:

EXAMPLE 1

a. A mixture of 540 g (4.0 moles) of 2-ethyl-6-methylaniline and 306 g(2.0 moles) of 2-bromo-1-methoxypropane is heated for 40 hours atreduced pressure (10 mm Hg) to 120°C with stirring. After it has cooled,the light red, viscous solution is diluted with 200 ml of water and madealkaline with 210 ml of conc. sodium hydroxide solution. Theprecipitated product is taken up in ether, and the ethereal solution iswashed neutral with water, dried, and evaporated.

Distillation of the residue yields pure 2-ethyl-6-methyl-N-[1'-methoxy-prop-2'-yl]-aniline which boils at 64°-66°C/0.07 Torr.

b. A solution of 9.7 g (0.047 mole) of the intermediate described undera) and 5.05 g (0.05 mole) of triethylamine in 30 ml of benzene istreated dropwise with a solution of 5.65 g (0.05 mole) of chloroacetylchloride in 10 ml of absolute benzene, and the mixture is furtherstirred for 2 hours at room temperature. The reaction mixture is dilutedwith ether, the solution repeatedly washed with water, and dried. Thesolvent mixture is evaporated off in vacuo to give pure2-ethyl-6-methyl-N-[1'-methoxy-prop-2'-yl]-chloroacetanilide, n_(D) ²⁰ :1.5301.

Analysis: calculated: C 63.5 H 7.8 N 4.9%. found: C 63.7 H 8.1 N 5.0%.The compound of the formula I exhibits a clear superiority overcompounds which are structurally or otherwise related and which are saidto have a good herbicidal properties. ##SPC7##

As has already been outlined in the introductory part of thisspecification comparative compound A belongs to a group which is said tohave unusually high activity at extremely low application rates.

Comparative compound B is included to verify the claim made at lines 5to 10 in column 14 of U.S. Pat. No. 3,547,620 that for effectiveness itis immaterial whether the haloacetyl is chloroacetyl or bromoacetyl."Compound C" is a mixture of the two isomers shown above which areenamines.

Although the formal representation of these isomers suuggests a closesimilarity between them and the compound of the invention, this ischemically not the case (cf. A. G. Cook, Ed. Marcel Dekker Ltd., NewYork and London, 1969). A description of a process for the preparationof the hitherto undescribed compound C follows.

Preparation of comparative substance C i. Starting material

163 g of titanium tetrachloride in 800 ml of toluene were added dropwiseto a solution of 229 g (1,64 mole) of 2-ethyl-6-methyl-cyclohexanon and435 g (4,9 mole) of 1-methyl-2-methoxy-ethylamine in 1000 ml toluene and110 ml of ether over a period of two hours with stirring and at atemperature of between 0°-10°C. After distilling off the ether thereaction mixture was refluxed for 61/2 hours. After cooling theprecipitate was filtered off and the filtrate concentrated in a rotaryevaporator at 50° C. Distillation of the residue under reduced pressuregave 174 g2-ethyl-6-methyl-N-(1-methyl-2-methoxy-ethyl)-cyclohexylidene-amine,m.p. 109°-113°C/15 Torr.

ii. End compound

174 g (0,83 mole) of2-ethyl-6-methyl-N-(1-methyl-2-methoxy-ethyl)-cyclohexylideneamine and101g (1 mole) of triethylamine were added dropwise one after the otherwith stirring and at a temperature of 5°C to a solution of 94 g (0,83mole) of chloroacetyl chloride in 3000 ml of benzene. The reactionmixture was then refluxed for 5 hours, cooled to room temperature,washed with water, dried with sodium sulfate, filtered and concentratedunder water-jet vacuum. Distillation of the residue under high vacuumgave 150,5 g of a 2-chloro-N-(1-methyl-2-methoxy-ethyl)N-(2-ethyl-6-methyl-cyclohexenyl)acetamide as amixture of its isomers b.p. 140°-148°/0.1 Torr.

    C.sub.15 H.sub.26 ClNO.sub.2                                                              C        H       Cl     N                                         Calculated  62,59    9,11    12,32  4,86 %                                    Found       62,7     9,4     12,2   5,0 %                                 

2-Ethyl-6-methyl-N-(1'-methoxyprop-2'-yl)-N-chloroacetanilide of theformula I is markedly superior to the structurally most closest knowncomparative compounds listed below in respect of all significantcriteria for a selective herbicide to wit activity, selectivity andstability as well with regard to its growth inhibiting properties onpost-emergent grass. ##SPC8##

EXAMPLE 2 Combating of weeds in various cultures of useful plants(preemergence method)

One day after the test plants have been sown in seed dishes (9.6 cmheight, 11 cm diameter at the top), dilute aqueous suspensions of theactive substances are sprayed in such concentrations on the surface ofthe soil as to correspond to rates of application of 2 kg, 1 kg, 0.5 kgand 0.25 kg per hectare. The seed dishes are kept at 19° to 21°C and50-60% relative humidity. The test is evaluated after 26 days accordingto the following rating:

9 = plants undamaged (as control test)

1 = plants destroyed

8-2 = intermediate stages of damage

- = not tested

The following weeds were employed in the tests.

Ipo = Ipomoea = Morning glory

Sin = Sinapis = Mustard

Ama = Amaranthus = Pigweed

Ses = Sesbania = Coffeeweed

Dat = Datura = Jimsonweed

Koch = Kochia = Kochia

Abu = Abutilon = Velvet leaf

Stell = Stellaria = Chickweed; Side = Teaweed

Chrys = Chrysanthemum segetum = Corn marigold

Avena = Avenafatua = Wild oat

Alo = Alopecurus = Black grass; Poa = Annual meadow grass

Fes = Festuca = Fescue

Sorg. alm= Sorghum almum = Sorghum almum

Pha = Phalaris = Canary grass

Sorg. hal= Sorghum halepense = Johnsongrass

Dig = Digitaria = Crabgrass

Pani = Panicum ramosum = Wild millet

Rott = Rottboellia = Raoul grass

Set = Setaria italica = Italian foxtail

Ech = Echinochloa crus-galli = Barnyard grass

The results are shown in the following 4 Tables:

a) Application rate: 2 kg/hectare

             Compd.                                                               Plant            I     A   B   C   D   E   F                                  ______________________________________                                        Corn         7     9     9   3   8   6   9                                    Soy beans    7     9     7   9   9   4   9                                    Beans        9     9     8   9   9   6   9                                    (Phaseolus)                                                                   Ipo          7     9     9   9   5   7   9                                    Sin          4     9     9   9   6   5   9                                    Ama          1     6     7   3   1   1   1                                    Ses          5     9     9   9   6   3   9                                    Dat          4     9     9   8   4   4   7                                    Koch         7     9     9   9   6   1   9                                    Abu          8     9     9   8   9   4   8                                    Stell        1     9     9   7   3   1   5                                    Sida         4     9     8   9   3   2   9                                    Chrys        3     9     9   8   3   2   9                                    Avena        2     9     8   4   4   1   9                                    Alo          2     9     3   1   2   1   6                                    Poa          2     9     3   1   1   1   3                                    Fes          1     9     1   1   1   1   1                                    Sorg.alm.    2     9     1   2   2   1   2                                    Pha          1     9     1   1   1   1   6                                    Sorg.hal.    1     9     2   1   1   1   4                                    Dig          1     8     2   1   1   1   1                                    Pani         1     9     1   1   1   1   2                                    Rott         2     9     8   7   7   3   9                                    Set          1     9     2   1   1   1   1                                    Ech          1     9     1   1   1   1   1                                    ______________________________________                                    

b) Application rate 1kg/hectare

             Compd.                                                               Plant            I     A   B   C   D   E   F                                  ______________________________________                                        Corn         7     9     9   4   9   8   9                                    Soybeans     8     9     8   9   9   4   9                                    Beans        9     9     8   9   9   6   9                                    (Phaseolus)                                                                   Ipo          9     9     9   9   7   9   9                                    Sin          6     9     9   9   8   6   9                                    Ama          1     9     7   5   1   1   3                                    Ses          6     9     9   9   7   3   9                                    Dat          4     9     9   9   4   4   7                                    Koch         9     9     9   9   6   1   9                                    Abu          8     9     9   9   --  4   9                                    Stell        2     9     9   9   5   2   6                                    Sida         4     9     9   9   4   3   9                                    Chrys        3     9     9   9   5   3   9                                    Avena        5     9     8   7   4   2   9                                    Alo          2     9     6   3   3   3   9                                    Poa          2     9     5   3   1   1   4                                    Fes          1     9     2   1   1   1   2                                    Sorg.alm     1     9     2   2   6   2   2                                    Pha          1     9     3   1   3   1   6                                    Sorg.hal     2     9     2   1   6   1   7                                    Dig          1     9     3   1   1   1   1                                    Pani         1     9     1   1   1   1   2                                    Rott         2     9     8   7   9   3   9                                    Set          1     9     5   2   1   1   2                                    Ech          1     9     2   1   1   1   2                                    ______________________________________                                    

c) Application rate 0.5 kg/hectare

             Compd.                                                               Plant            I     A   B   C   D   E   F                                  ______________________________________                                        Corn         9     9     9   7   9   9   9                                    Soybeans     9     9     8   9   9   7   9                                    Beans        9     9     9   9   9   8   9                                    (Phaseolus)                                                                   Ipo          9     9     9   9   7   9   9                                    Sin          8     9     9   9   8   8   9                                    Ama          1     9     8   8   1   1   4                                    Ses          9     9     9   9   8   7   9                                    Dat          5     9     9   9   6   7   9                                    Koch         9     9     9   9   7   2   9                                    Abu          8     9     9   9   9   7   9                                    Stell        2     9     9   9   6   2   8                                    Sida         7     9     9   9   4   5   9                                    Chrys        8     9     9   9   5   6   9                                    Avena        6     9     9   9   6   5   9                                    Alo          4     9     9   7   4   3   9                                    Poa          3     9     8   6   1   1   6                                    Fes          1     9     3   1   1   1   2                                    Sorg.alm     2     9     6   2   6   2   7                                    Pha          2     9     7   1   4   1   7                                    Sorg.hal     2     9     6   1   6   1   8                                    Dig          1     9     4   1   1   1   1                                    Pani         1     9     2   1   1   1   7                                    Rott         7     9     9   9   9   6   9                                    Set          1     9     5   2   1   1   3                                    Ech          1     9     2   2   1   1   3                                    ______________________________________                                    

d) Application rate 0.25 kg/hectare

             Compd.                                                               Plant            I     A   B   C   D   E   F                                  ______________________________________                                        Corn         9     9     9   8   9   9   9                                    Soybeans     9     9     9   9   9   8   9                                    Beans        9     9     9   9   9   9   9                                    (Phaseolus)                                                                   Ipo          9     9     9   9   8   9   9                                    Sin          8     9     9   9   8   9   9                                    Ama          1     9     9   9   1   1   5                                    Ses          9     9     9   9   8   9   9                                    Dat          5     9     9   9   6   9   9                                    Koch         9     9     9   9   8   5   9                                    Abu          8     9     9   9   9   7   9                                    Stell        4     9     9   9   8   3   9                                    Sida         8     9     9   9   7   7   9                                    Chrys        9     9     9   9   7   7   9                                    Avena        7     9     9   9   8   5   9                                    Alo          6     9     9   9   6   4   9                                    Poa          3     9     9   9   3   1   7                                    Fes          1     9     4   3   1   1   2                                    Sorg.alm     2     9     7   2   6   2   9                                    Pha          2     9     7   2   5   1   9                                    Sorg.hal     2     9     8   1   6   1   9                                    Dig.         1     9     6   1   1   1   3                                    Pani         1     9     3   4   1   1   8                                    Rott         8     9     9   9   9   8   9                                    Set          1     9     7   2   1   1   5                                    Ech          1     9     4   3   1   1   3                                    ______________________________________                                    

EXAMPLE 3

The following tests compare the compound of the invention withcomparative compounds D, E and F with respect to in-soil stability onpre-emergent application.

Arable soil comprising ca.4 % organic substance, 21 % clay, 32 % siltand 43 % sand and contained in a plastic basin (50 cm × 32 cm × 7 cm)was sprayed with testsubstance in the form of a broth prepared from anemulsion concentrate to give an active substance concentrationequivalent to 2, 1 and 0.5 kg/hectare. Two parallel rows of weeds weresown in each basin and a further two rows were sown weekly over the next6 weeks. Setaria italica was chosen as test weed since it is especiallysensitive to compounds of type under test.

The condition of the weeds in each set of two rows was evaluated 3 weeksafter sowing. The test conditions were: temp. 19°-23°C; rel. humidity50°-60°%; watering - normal.

Key as in example 2.

a) Application rate: 2 kg/hectare

            Weeks                                                                 Compd.          0     1   2   3   4   5   6                                   ______________________________________                                        I           1     1     1   1   2   1   2                                     C           1     1     1   1   3   4   6                                     D           1     1     1   2   3   5   9                                     E           1     1     2   5   9   9   9                                     F           2     1     3   4   5   5   6                                     ______________________________________                                    

b) Application rate: 1 kg/hectare

            Weeks                                                                 Compd.          0     1   2   3   4   5   6                                   ______________________________________                                        I           1     1     3   3   3   2   4                                     C           1     1     4   4   6   8   9                                     D           2     2     2   4   4   9   9                                     E           1     2     8   9   9   9   9                                     F           2     3     4   5   5   8   9                                     ______________________________________                                    

c) Application rate: 0.5 kg/hectare

            Weeks                                                                 Compd           0     1   2   3   4   5   6                                   ______________________________________                                        I           2     2     4   4   4   4   8                                     C           2     2     5   6   8   9   9                                     D           2     5     8   8   9   9   9                                     E           1     5     6   9   9   9   9                                     F           4     4     8   9   9   9   9                                     ______________________________________                                    

EXAMPLE 4 Growth inhibition in grasses (postemergence method)

Seeds of the grasses Lolium perenne, Poa pratensis, Festuca ovina, andDactylis glomerata were sown in plastic dishes filled with anearth/turf/sand mixture. After 3 weeks the germinated grasses were cutback to a height of 4 cm above the soil and 2 days later sprayed withaqueous spray broths of active substances of the formula I. The amountof active substance corresponded to a rate of application of 5 kg ofactive substance per hectare. 21 days after application the growth ofthe grasses was evaluated according to the following linear rating:

1 = strong inhibition (no growth from the time of application)

9 = no inhibition (growth as untreated control)

The following results were obtained:Com- Lolium Poa FestucaDactylispound perenne pratensis ovinaglomerata______________________________________I 2 3 1 6C 7 9 9 9D 4 3 33E 7 6 7 8F 7 6 6 9______________________________________

None of the comparative compounds C, E and F has useful growth retardingproperties. Only compound D has an activity equivalent to that ofcompound I. However, the fast degradation of compound D in the soilmakes it unsuitable for practical use.

The agents according to the invention are manufactured in known mannerby intimately mixing and/or grinding active substances of the formula Iwith the suitable carriers, optionally with the addition of dispersantsor solvents which are inert towards the active substances. The activesubstances may take and be used in the following forms:

Solid forms:

dusts, tracking agents, granules, coated granules, impregnated granulesand homogeneous granules.

Liquid forms:

a. active substances which are dispersible in water: wettable powders,pastes, emulsions;

b. solutions.

To manufacture solide forms (dusts, tracking agents), the activesubstances are mixed with solid carriers. Suitable carriers are, forexample: kaolin, talcum, bolus, loess, chalk, limestone, groundlimestone, attaclay, dolomite, diatomacous earth, precipitated silica,alkaline earth silicates, sodium and potassium aluminium silicates(feldspar and mica), calcium and magnesium sulphates, magnesium oxide,ground synthetic materials, fertilisers, for example ammonium sulphate,ammonium phosphate, ammonium nitrate, urea, ground vegetable products,such as corn meal, bark dust, sawdust, nutshell meal, cellulose powder,residues of plant extractions, activated charcoal etc. These substancescan either be used singly or in admixture with one another.

The particle size of the carriers for dusts is advantageously up to 0.1mm, for tracking agents from about 0.075 to 0.2 mm, and for granules 0.2mm or larger.

The solid forms contain the active substances in concentrations from0.1% to 80%.

To these mixtures can also be added additives which stabilize the activesubstance and/or non-ionic, anionic and cationic surface activesubstances, which for example improve the adhesion of the activeingredients on plants or parts of plants (adhesive and agglutinants)and/or ensure a better wettability (wetting agents) and dispersibility(dispersing agents). Examples of suitable adhesives are the following:olein/chalk mixture, cellulose derivatives (methyl cellulose,carboxymethyl cellulose), hydroxyethyl glycol ethers of monoalkyl anddialkyl phenols having 5 to 15 ethylene oxide radicals per molecule and8 to 9 carbon atoms in the alkyl radical, lignin sulphonic acids, theiralkali metal and alkaline earth metal salts, polyethylene glycol ethers(carbowaxes), fatty alcohol polyethylene glycol ether having 5 to 20ethylene oxide radicals per molecule and 8 to 18 carbon atoms in thefatty alcohol moiety, condensation product of urea and formaldehyde, andalso latex products. Preferred dispersions (suspensions and emulsions)are manufactured by mixing or grinding the active substance withcarriers accompanied by the addition of dispersing agents and solvents,in the process of which there result firstly dispersible activesubstance concentrations, such as wettable powders and emulsifiableconcentrates.

The water-dispersible concentrates of the active substance i.e. wettablepowders, pastes and emulsifiable concentrates, are agents which can bediluted with water to any concentration desired. They consist of activesubstance, carrier, optionally additives which stabilize the activesubstance, surface-active substances and anti-foam agents and,optionally, solvents. The active substance concentrations in theseagents are from 5-80%.

Wettable powders and pastes are obtained by mixing and grinding theactive substances with dispersing agents and pulverulent carriers insuitable apparatus until homogeneity is attained. Carriers are, forexample, those mentioned for the solid forms of application. In somecases it is advantageous to use mixtures of different carriers. Asdispersing agents there can be used, for example, condensation productsof sulphonated naphthalene and sulphonated naphthalene derivatives withformaldehyde, condensation products of naphthalene or naphthalenesulphonic acids with phenol and formaldehyde, as well as alkali,ammonium and alkaline earth metal salts of lignin sulphonic acid, inaddition, alkylaryl sulphonates, alkali and alkaline earth metal saltsof dibutyl naphthalene sulphonic acid, fatty alcohol sulphates such assalts of sulphated hexadecanols, heptadecanols, octadecanols, and saltsof sulphated fatty alcohol glycol ethers, the sodium salt of oleoylethionate, the sodium salt of oleoyl methyl tauride, ditertiaryacetalene glycols, dialkyl dilauryl ammonium chloride and fatty acidalkali and alkaline earth metal salts.

Suitable anti-foam agents are silicones. The active substance is somixed, groud sieved and strained with the additives mentioned abovethat, in wettable powders, the solid particle size of from 0.02 to 0.04and in pastes, of 0.03 is not exeeded. To produce emulsifiableconcentrates and pastes, dispersing agents such as those given in theprevious paragraphs, organic solvents and water are used. Examples ofsuitable solvents are the following: alcohols, benzene, xylenes,toluene, dimethyl sulphoxide, N.N-dialkylated amides, N-oxides of amines(whereas N-oxides of trialkylamines are preferred), and mineral oilfractions boiling between 120° and 350°C. The solvents must bepractically odorless, not phytotoxic, inert to the active substances andnot readily inflammable.

Furthermore, the agents according to the invention can be applied in theform of solutions. For this purpose the active substance or severalactive substances of general formula I are dissolved in suitable organicsolvents, mixtures of solvents or in water. Aliphatic and aromatichydrocarbons, chlorinated derivatives thereof, alkyl naphthalenes andmineral oils singly or in admixture, can be used as organic solvents.The solutions contain the active substance in a concentration range from1 to 20%.

The agents described according to the invention can be mixed with otherbiocidally active substances or agents. Thus in order to broaden theactivity spectrum the new agents may contain, for example, insecticides,fungicides, bactericides, fungistatics, bacteriostatics, nematocides orfurther herbicides, in addition to the cited active substances of theformula I. The agents according to the invention may also contain plantfertilisers, trace elements etc.

The active substances of the formula I can, for example, be formulatedas follows. The parts denote parts by weight.

Granules

The following substances are used to manufacture 5% granules:

5 parts of2-Ethyl-6-methyl-N-(1'-methoxyprop-2'-yl)-N-chloroacetanilide,

0.25 parts of epichlorohydrin,

0.25 parts of cetyl polyglycol ether,

3.50 parts of polyethylene glycol ether,

91 parts of kaolin (particle size: 0.3- 0.8 mm).

The active substance is mixed with epichlorohydrin and the mixturedissolved in 6 parts of acetone, then polyethylene glycol ether andcetyl polyglycol ether are added. The resulting solution is sprayed onkaolin and then evaporated in vacuo.

Wettable powder

The following constituents are used to manufacture (a) a 50%, (b) a 25%and (c) a 10% wettable powder:

a.

50 parts of2-Ethyl-6-methyl-N-(1'-methoxyprop-2'-yl)-N-chloroacetanilide,

5 parts of sodium dibutylnaphthalene sulphonate,

3 parts of naphthalenesulphonic acid/phenolsulphonic acid/formaldehydecondensate (3:2:1),

20 parts of kaolin,

22 parts of Champagne chalk;

b.

25 parts of2-Ethyl-6-methyl-N-(1'-methoxyprop-2'-yl)-N-chloroacetanilide,

5 parts of oleylmethyltaurid-sodium-salt,

2.5 parts of naphthalenesulphonic acid/formaldehyde condensate,

0.5 part of carboxymethyl cellulose,

5 parts of neutral potassium-aluminium-silicate,

62 parts of kaolin;

c.

10 parts of compound I

3 parts of a mixture of the sodium salts of saturated fatty alcoholsulphates,

5 parts of naphthalenesulphonic acid/formaldehyde condensate,

82 parts of kaolin.

The indicated active substance is applied to the corresponding carriers(kaolin and chalk and then these are mixed and ground, to yield wettablepowders of excellent wettability and having an excellent capacity forforming suspensions. By diluting these wettable powders with the 10-foldamount of water it is possible to obtain suspensions of any desiredconcentration.

Paste

The following substances are used to manufacture a 45% paste:

45 parts of compound I

5 parts of sodium aluminium silicate,

14 parts of cetyl polyglycol ether with 8 mols of ethylene oxide,

1 part of oleyl polyglycol ether with 5 mols of ethylene oxide,

2 parts of spindle oil,

10 parts of polyethylene glycol,

23 parts of water.

The active substance is intimately mixed with the addition inappropriate devices and ground. A paste is obtained from which, bydiluting it with water, is possible to manufacture suspensions of everydesired concentration of active substance.

Emulsion Concentrate

To manufacture a 25% emulsion concentrate

25 parts of compound I

5 parts of a mixture of nonylphenolpolyoxy-ethoxyethylene and calciumdodecylenesulphonate,

35 parts of 3,5,5-trimethyl-2-cyclohexan-1-one,

35 parts of dimethyl formamide,

are mixed together. This concentrate can be diluted with water to giveemulsions in desired concentrations. Such emulsions are suitable forcombating weeds in cultures of crop plants.

What we claim is:
 1. The compound2-ethyl-6-methyl-N-(1'-methoxyprop-2'-yl)-N-chloroacetanilide of theformula ##SPC9##